The main subdivision of global environment which includes all water is termed as

The main subdivision of global environment which includes all water is termed as Hydrosphere.
The hydrosphere is the combined mass of water found on, under, and above the surface of a planet, minor planet, or natural satellite.
It has been estimated that there are 1.386 billion cubic kilometres of water on Earth. This includes water in gaseous, liquid and frozen forms as soil moisture, groundwater, oceans and seas, lakes, rivers and streams, wetlands, glaciers, ice and snow cover on Earth's surface; vapour, droplets and crystals in the air; and part of living plants, animals and unicellular organisms of the biosphere.